Fatty acids, C16-18 (even numbered), reaction products with diethylene triamine, di-Me sulfate quaternized

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-11-08 to 2018-04-13

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

adopted on 27 July 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

30 May 2008

Deviations:

no

GLP compliance:

no

Type of method:

differential scanning calorimetry

Key result

Melting / freezing pt.:

> 9 - < 63 °C

Atm. press.:

1 013 Pa

Decomposition:

yes

Decomp. temp.:

>= 280 °C

Sublimation:

no

Remarks on result:

other:

Remarks:

The substance is a mixture of substances with various alky chain length, thus a defined melting point could not be detected.

According to the visual inspection, the test item liquefies at 77 °C. At the DSC tests no particular melting point, but a melting range was detected, which was to be expected as test substance is a mixture of substances with various alky chain length. For the determination of the melting range, the main DSC test was performed in triplicate. The melting ranges were read from the second and the third heating run of each test as the peak top temperature of the allocated melting peak.

After the test procedure, the samples were re-weighed in order to check for a significant sample loss indicating potential interfering non-melting processes. For none of the samples a significant weight loss was recorded (< 0.5 %).

Conclusions:

A defined melting point is not assessable, a melting range which can be explained by the broad chain length variety of the alkyl moieties, is reported instead. As an average, a melting range of 9 °C to 63 °C was measured by DSC which is lower as the clear point of 77 °C recorded at the visual observation, however, this may be falsified by by-products.

Executive summary:

In study performed according to OECD guideline 102 the melting point of the test substance was investigated by differential scanning calorimetry and thermogravimetric measurement. At the main DSC tests, an endothermic signal was recorded over a temperature range of 9 °C to 63 °C, which can be attributed to the melting procedure as in the DSC main tests corresponding comparable exothermic signals were recorded.

The broad temperature range at which the melting process was detected can be explained by the broad chain length variety of the alkyl moieties. Thus, a defined melting point is not assessable, a melting range is reported instead.

As an average, a melting range of 9 °C to 63 °C was measured by DSC which is lower as the clear point of 77 °C recorded at the visual observation, however, this may be falsified by by-products.

Since the substance is an UVCB, the starting melting point of the main constituents can be assumed to be at 63°C.

The recorded main weight loss above 306.4 °C (estimated onset on TGA) may indicate a beginning evaporation (boiling), however, from the knowledge of the chemical structures this endotherm is most likely allocated to a degradation process.

This assumption can also be deduced from the literature, as it is well known that quaternary structures tend to degrade above temperatures of 120 °C (Hoffmann degradation; reversed Menshutkin reaction).  

In order to provide evidence for this assumption, a degradation test was performed during which an aliquot of the sample was heated to 280 °C for 15 minutes. The remaining residue (97 % of the original material) war characterised by NMR spectroscopy. The NMR analysis confirms the decomposition of the product. Consequently, hydrogenated tallow/nortallow based IQAC does not provide a boiling point until disintegration at about 280 °C.

Description of key information

- study conducted according to OECD guideline 102, differential scanning calorimetry, thermogravimetriv measurement, capillary method, based on different methods used the melting point is considered to be between 9 and 63°C, the clear point of 77 °C was recorded at the visual observation

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

63 °C

Additional information

In study performed according to OECD guideline 102 the melting point of the test substance was investigated by differential scanning calorimetry and thermogravimetric measurement. At the main DSC tests, an endothermic signal was recorded over a temperature range of 9 °C to 63 °C, which can be attributed to the melting procedure as in the DSC main tests corresponding comparable exothermic signals were recorded.

The broad temperature range at which the melting process was detected can be explained by the broad chain length variety of the alkyl moieties. Thus, a defined melting point is not assessable, a melting range is reported instead.

As an average, a melting range of 9 °C to 63 °C was measured by DSC which is lower as the clear point of 77 °C recorded at the visual observation, however, this may be falsified by by-products. Since the substance is an UVCB, the starting melting point of the main constituents can be assumed to be at 63°C.